Matter Conveyance System

ABSTRACT

A matter conveyance system is located within a catheter and transports thrombus from a proximal portion of the catheter to a distal end of the catheter. In one example, the matter conveyance system is a screw or helix that rotates to cause movement of the thrombus.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application Ser.No. 61/730,923 filed Nov. 28, 2012 entitled Matter Conveyance System,which is hereby incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

Buildup of thrombus in the vascular system, especially in theneurovascular system, can lead to clot formation. Clot formation canlead to disrupted blood flow, including ischemia, and may eventuallylead to a stroke. Recent technologies utilize clot retrieval devicesdesigned to grasp and remove the clot from the body. These clotretrieval devices are delivered through a delivery system, such as acatheter. Maceration or fragmentation of the clot is a significant issueduring the clot retrieval and withdrawal operation. Fragmented thrombusmay migrate further down the bloodstream and reform as a clot. A devicewhich would minimize risk of maceration during clot retrieval andwithdrawal operations is therefore desirable.

SUMMARY OF THE INVENTION

One embodiment of the present invention is directed to a matterconveyance system to aid in retrieval of matter and/or thrombus from thevascular system of a patient. The matter conveyance system is locatedwithin a delivery device, such as a catheter, and helps move matterthrough the delivery device. In one embodiment, the conveyer systemincludes a shaft, a screw connected to said shaft, a mechanism to rotatethe shaft and screw, an introducer sleeve, and aspiration device.

The screw can be located within a substantial portion of the catheter,within only a distal portion of the catheter, beyond the distal end ofthe catheter tubing, or proximal to the distal end of the cathetertubing.

In another embodiment, the screw of the matter conveyance system definesa solid lumen through which other devices may be transmitted through.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects, features and advantages of which embodiments ofthe invention are capable of will be apparent and elucidated from thefollowing description of embodiments of the present invention, referencebeing made to the accompanying drawings, in which

FIG. 1 illustrates a catheter utilizing a conveyer system.

FIG. 2 illustrates another view of the catheter utilizing the conveyersystem of FIG. 1.

FIGS. 3-6 illustrate a screw used in a conveyer system.

FIG. 7-11 illustrate various sections of the catheter utilizing theconveyer system of FIG. 2.

FIG. 12 illustrates an introducer sleeve used in a conveyer system.

FIG. 13 illustrates an end view of the screw shown in FIGS. 3-6.

FIG. 14 illustrates a motorized device for rotating a conveyer system.

DESCRIPTION OF EMBODIMENTS

Specific embodiments of the invention will now be described withreference to the accompanying drawings. This invention may, however, beembodied in many different forms and should not be construed as limitedto the embodiments set forth herein; rather, these embodiments areprovided so that this disclosure will be thorough and complete, and willfully convey the scope of the invention to those skilled in the art. Theterminology used in the detailed description of the embodimentsillustrated in the accompanying drawings is not intended to be limitingof the invention. In the drawings, like numbers refer to like elements.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art andwill not be interpreted in an idealized or overly formal sense unlessexpressly so defined herein.

For purposes of terminology presented below and above, clot and thrombuscan be used synonymously. Matter can refer to thrombus, clots, otherobstructions, foreign body material, or other material which may beencountered within the vasculature. The terms proximal and distal asused below generally refer to areas of the catheter and/or matterconveyance system as deployed in the vasculature. Delivery device mayconnote catheters, sheaths, hypotubes, and the like. The term cathetercan also be construed liberally as applying to sheaths, hypotube, otherdelivery devices, and the like.

FIGS. 1 and 2 illustrate a catheter 10 utilizing a matter conveyancesystem for capturing and conveying matter (e.g., a clot or otherbiological material within a patient's vessels) at a distal end of thecatheter 10 towards its proximal end. The matter conveyance systemincludes a screw 20 which is located within a portion of the catheter 10and sits within the catheter tubing 12. The screw 20 is connected to ashaft 22 that extends out a proximal end of the catheter 10, allowingfor engagement with a motor for causing rotation of the screw 20. Whenrotated, the screw 20 functions similar to an auger or Archimedes screw,linearly moving any enclosed objects towards a proximal end of thecatheter. In other words, matter pulled into the catheter tubing 12becomes captured between the wall of the tubing 12 and the loops of thescrew 20, the loops of the screw 20 to push the matter in a proximaldirection as the screw rotates.

In one example, aspiration (i.e. suction) can be used to pull the matterwithin the distal end of the catheter's tubing 12 and further assist therotation of the screw 20 to displace the matter proximally through thecatheter. In one example, the aspiration can be applied by advancing asmaller diameter tube into port 18 and through the catheter 10 to apoint just external of the catheter's distal end, thereby allowing thesuction to engage the matter. In this regard, the tube can subsequentlybe retracted (or simply left in place and deactivated) and the rotationof the screw used to displace the clot or matter proximally through thecatheter 10. Alternatively, the aspiration tube can be applied near aproximal end of the catheter tube 12 (e.g., directly to port 18),thereby assisting the screw 20 in displacing the matter through the restof the catheter 10.

In one example, the shaft 22 and screw 20 are separate components whichare mated together by a process such as welding, or other adhesive orbonding techniques. In another example a tube can be processed to createan integral shaft and screw component, such as via laser-cutting,etching or similar techniques.

The screw 20 may take on a variety of shapes and/or angles in itsprofile, including a helix, and/or the traditional spiral shape commonto augers/Archimedes screws. Preferably, the screw 20 is shaped suchthat it forms an internal passage, lumen, or throughway 21 along itslength, as seen in FIGS. 3-6 and particularly in FIG. 13. This lumen 21allows devices, such as a guidewire or an aspiration tube to passthrough both the screw 20 and the catheter 10 during various portions ofa procedure.

In the embodiment of FIGS. 3-6 and 13, the lumen 21 is formed entirelyfrom the loops of the screw. However, a closed lumen configuration isalso possible, in which a cylindrically (or other) shaped lumensurrounds the external screw diameter. In other words, the threads ofthe screw 20 could be fixed against an outer tube that rotates with thescrew threads. Such an outer tube may extend along the entire length ofthe screw threads or a fractional length.

For example, the lumen could extend from the distal end of the shaft 22to the distal end of the screw 20. Alternately, it could extend from thedistal end of the shaft 22 to a point before the distal end of the screw20. Alternately, it could extend from any point proximal from the distalend of the screw 20 to the distal end of the screw 20. Alternatelystill, the outer lumen could be segmented along the length of the screw20. The closed lumen screw configuration could be formed by placing ahollow tube external to the screw and mating the pieces together bywelding or other techniques. Alternately, the screw configuration couldbe cut from the tube, leaving a closed lumen with a screw pattern formedtherein via laser cutting or similar techniques. In another example, theshaft 22 also has a lumen to accommodate various devices (e.g. aguidewire), such that a device can pass through the shaft 22 and intothe lumen of the screw 20.

The screw 20, outer tube, and shaft 22 can be made from a variety ofmaterials including but not limited to tempered spring steel, stainlesssteel, similar metals, or a variety of polymers including polyethylene,UHMWPE, PVC, ABS, etc.

Returning to FIGS. 1-2, the catheter tubing 12 includes a luer adapter14 connected to hemostasis or hemostatic valve 16. The hemostatic valve16 contains a port 18 that can be used with an air source for aspiration(as previously discussed) or to inject contrast to aid in visualization.Hemostatic valve 16 and luer adapter 14 both have a lumen runningthrough them to accommodate the matter conveyance system.

Screw 20 can be located along the entire length of the catheter or anyfractional portion thereof. For example, the distal end of the screw 20may be located at or near the distal end of the catheter tubing 12,while the proximal end of the screw 20 may be located at or near theproximal end of the hemostatic valve 16.

The proximal end of the screw 20 preferably connects to shaft 22 (seenbest in FIGS. 1-4) at a proximal portion of the catheter 10 such thatthe shaft 22 extends out of the catheter's proximal end. In oneembodiment, the shaft 22 is connected to a handheld device 40, shown inFIG. 14 for the purposes of rotating shaft 22 and screw 20. Preferably,the device 40 includes a motor 46 that is engaged with the shaft 22, anda button 44 for starting and stopping rotation. Optionally, the device40 may also include a button or switch for changing a direction ofrotation of the screw 20. In one embodiment, the shaft 22 can beinserted into and removed from an aperture 42 on the device 40. Inanother embodiment, the shaft 22 is permanently fixed to the device 40and cannot be removed by the user.

In another embodiment, the handheld device 40 further comprises anon-electrical, manual, mechanical rotation mechanism, such as ahand-crank, dial, or outer rotating tube. The handheld device 40 mayinclude this mechanical rotation mechanism on its own or as a secondarymechanism in addition to the previously described motor 46.

Turning to FIG. 7, the distal end of the catheter 10 includes cathetertubing 12 which has an internal passage with a larger diameter than theouter diameter of the screw 20, thereby allowing the screw 20 to rotate.The screw 20 extends through the length of the tubing 12, through thehemostatic valve 16, and merges into the shaft 22 shortly before aflared end 30. However, the length of the screw section and shaftsection can be customized.

As best seen in FIGS. 1, 2, and 8, the luer adapter 14 connects thecatheter tubing 12 with the hemostatic valve 16. Specifically, thedistal end of the luer adapter 14 is connected to the proximal end ofthe catheter tubing 12 while the proximal end of the luer adapter 14 isconnected to the hemostatic valve 16.

As best seen in FIG. 8, the hemostatic valve 16 allows various devices,such as a guidewire, the screw 20, and the introducer sleeve 24 to enterthe catheter tubing 12 without substantial proximal blood leakage. Whilea wide variety of different hemostatic valves can be used according tothe present invention, the present embodiment of the hemostatic valve 16is generally known as a Y-adapter valve since it includes a main bodyportion 37 and a secondary port 18. The valve 16 further includes a luerlock portion 36 at the distal end of the body portion 37 that engagesthe luer adapter 14 and further contains a seal. An adjustable valve 38is located at the proximal end of the body portion 37, allowing the endof the body portion 37 to be sealed off completely when not in use or toseal around an inserted device.

The main body portion 37 of the hemostatic valve 16 contains a channelsized to accommodate an introducer sleeve 24 (best shown in FIGS. 8-12)that is inserted into the channel to provide a guide path and to allowrotation of screw 20. The slots 26 of the introducer sleeve 24 allow foraspiration via port 18 to aid in pulling the matter through the catheter10 while also providing visibility within the sleeve 24 to determinewhether or not the matter has been pulled into the hemostatic valve 16.In one embodiment, the introducer sleeve 24 is a hypotube with a numberof slots 26 located along the length of the sleeve 24 in one or morerows (e.g., 2 or 4 rows on opposite sides of the sleeve 24). Theintroducer sleeve 24 may be made out of various materials such asstainless steel or a rigid polymer.

The conveyance system further includes a seal assembly 27 (seen best inFIGS. 10 and 11), which ensures that contrast or other lytic agents canbe injected through the catheter 10 (via port 18) without the need toremove the matter conveyance system. Seal assembly 27 also ensures thatany aspiration (via port 18) used to help pull the matter through thesystem will be effective at creating suction. The seal assembly 27creates a pressure buildup at the proximal-most end of the system,therefore allowing any lytic agents to naturally flow distally—or awayfrom—seal assembly 27 and towards catheter tubing 12. Similarly, anyaspiration or negative air pressure source used to aid in retrievaloperations will pull in a direction from the catheter tubing 12 towardsthe seal assembly 27, in a distal to proximal direction.

In the present embodiment, the seal assembly 27 includes a cylindricalhousing 28 having a circular slot 28A sized for a seal member 30. Theseal member 30 is positioned such that it engages and seals against theshaft 22, thereby preventing any fluid from moving out of the end of thesleeve 24. In one embodiment, the seal assembly 27 could be connected toor integrated with the handheld device 40.

In one embodiment, the matter conveyance system sits within a guidecatheter and thus avoids the need of a microcatheter to deliver andretrieve a clot retrieval device. A guidewire can also be used with thesystem as follows. Due to the shape of the screw 20 (as shown in FIGS.11 and 13) which leaves a large center region open 21, the guidewire canpass through the screw 20.

Referring to FIGS. 8-9, a guidewire can be advanced through port 18 andinto the introducer sleeve can be rotated/manipulated such that slot 26of introducer sleeve 24 corresponds with the through-hole of port 18 sothat an inserted guidewire will pass through slot 26. The guidewire canthen be pushed through the guide catheter 10 and will pass through theopen center region of the screw all the way past the distal end of themicrocatheter 10. When the aspiration means are used to provide suctionto engage the thrombus, and the thrombus is engaged and brought back tothe distal end of the guide catheter, the conveyance system can beactivated to pull the thrombus all the way back through the catheter 10.

Alternatively, another RHV (rotating hemostatic valve) can be placeddistal to the motor, and the guidewire can be placed through a port onthis more distal RHV. In this configuration a lumen will run through thecomplete length of the system so that the guidewire can pass through thelength of the screw 20 (i.e. the open-channel screw would run all theway from the proximal end to the distal end of the matter conveyancesystem).

In another embodiment, the matter conveyance system can be used in asmaller sheath that is delivered through a guide catheter. A sheath,hypotube, smaller catheter, or microcatheter can be placed through theguide catheter. Such a configuration might be useful for engagingsmaller regions of matter or thrombus buildup. Aspiration means may bedelivered through the microcatheter to engage the matter or thrombus,and the screw may be used to move the matter or thrombus through themicrocatheter.

In another embodiment, a portion of the screw in the matter conveyancesystem can utilize a solid, hypotube profile while still retaining theinner open lumen to preserve accessibility of the guidewire through itscenter passage. The hypotube section will provide some increasedstructural strength to the entire screw due to the more rigid profileshape. In one example, the entire screw is laser-cut and the hypotubesection is laser-cut to a lesser extent, leaving a solid-channelhypotube section and an open-channel screw section.

Another embodiment involves only a distal portion of screw 20functioning to convey matter. In this embodiment, shaft 22 could beextended such that screw 20 runs through only a distal portion of thedevice (i.e. only through a portion of the tubing 12). Alternatively, ahypotube could be placed over the proximal portion of screw 20 leavingonly the distal portion of the screw 20 with the configuration whichwill allow conveyance. In this embodiment, the screw is used to conveythe matter from only a distal portion to more proximal portion of thecatheter (instead of all the way through the catheter). The cathetercould be removed entirely from the vasculature to remove the matter oncethe matter reaches a proximal portion of the catheter.

In another embodiment, screw 20 may extend past the distal end ofcatheter tubing 12. This configuration would enable the screw 20 tograsp matter within the matter conveyance system before said objectsenter the catheter, then help move said objects through the catheter.This configuration could also be useful for using screw 20 as a clotdisruptor. Since screw 20 extends past distal end of catheter tubing 12,it would be positioned in the vasculature. Thus it could engage with aclot or matter, allowing rotation of the screw to extract a portion ofthe clot as well as convey the engaged clot to a proximal positionwithin the catheter via the matter conveyance system.

In another embodiment screw 20 may not run all the way through thedistal end of catheter tubing 12. In this configuration, matter would bepulled through a portion of the catheter, until engaged with screw 20,and then is conveyed through the catheter via the matter conveyancesystem.

In another embodiment, the inner diameter or passage 21 of screw 20 maydefine another interior lumen used to deliver other devices. In oneexample, the inner lumen 21 is machined when creating the screw tointroduce an inner lumen 21 consistent with the material used to makethe screw.

In another example, the screw has a permanent polymer or metallic lumenaffixed within the inner diameter/passage 21 of the screw whichfunctions similar to a microcatheter positioned within the guidecatheter. This lumen could extend throughout the entire length of thescrew, or just along a more proximal portion of the screw. In anotherexample, the inner screw diameter 21 accommodates a removablemicrocatheter which can be pushed through and pulled out of the interiorof the screw. This lumen may be used to deliver the guidewire and mayalso be used to deliver a clot retrieval device. Such clot retrievaldevices may be mechanical systems used to physically grasp the clot andare typically delivered through a microcatheter. With this embodimentthe inner lumen of the screw would act like a microcatheter and could beused to deliver a clot retrieval device to a particular site within thevasculature. The aspiration means could also be delivered through thisclosed lumen.

In one example, the outer screw diameter is between about 0.017″ to0.068″. Since the screw fits within the catheter 10, the catheter innerand outer diameter will be larger than the screw diameter. Thus, in oneexample, the screw 20 fits in a catheter 10 sized anywhere from about0.021″ for the outer diameter to about 0.09″ for the outer diameter. Thepitch of the screw 20 can be as low as almost zero (closed pitch) toabout 0.2″. The screw thickness can be about 0.005″ to 0.5″. In oneexample the screw pitch is about 0.07″, thickness is about 0.02″, theouter diameter is about 0.068″ and inner diameter (found by subtractingthe overall screw lumen thickness from the outer diameter) is about0.028″. These values are offered up as illustrative examples and are notmeant to define or limit the matter conveyance system in any way.

Although the invention has been described in terms of particularembodiments and applications, one of ordinary skill in the art, in lightof this teaching, can generate additional embodiments and modificationswithout departing from the spirit of or exceeding the scope of theclaimed invention. Accordingly, it is to be understood that the drawingsand descriptions herein are proffered by way of example to facilitatecomprehension of the invention and should not be construed to limit thescope thereof.

What is claimed is:
 1. A biological conveyance system, comprising: anelongated screw having a proximal end and a distal end; said elongatedscrew locatable within a catheter; a rotation mechanism coupled to saidproximal end of said elongated screw and configured to rotate saidelongated screw so as to retract biological material located within apatient.
 2. The biological conveyance system of claim 1, wherein saidelongated screw has a helix shape that forms an internal passage along alength of said elongated screw.
 3. The biological conveyance system ofclaim 1, wherein said elongated screw is positioned inside a cathetersleeve.
 4. The biological conveyance system of claim 1, wherein saiddistal end of said elongated screw is positioned within and proximate toa distal end of a catheter sleeve.
 5. The biological conveyance systemof claim 1, wherein said elongated screw further comprises a shaft fixedto said proximal end of said elongated screw and to said rotationmechanism.
 6. The biological conveyance system of claim 1, wherein saidelongated screw is located within a catheter sleeve, a luer, and ahemostasis valve.
 7. The biological conveyance system of claim 6,further comprising a slotted sleeve disposed over a proximal end of saidelongated screw and within said hemostasis valve.
 8. The biologicalconveyance system of claim 7, wherein said hemostasis valve is Y-adaptervalve.
 9. The biological conveyance system of claim 8, furthercomprising a seal adapter located on said proximal end of said screw anda proximal end of said slotted sleeve.
 10. The biological conveyancesystem of claim 9, further comprising an aspiration device connected toa secondary port on said hemostasis valve.
 11. The biological conveyancesystem of claim 1, wherein said rotation mechanism comprises a motorizedrotation mechanism, a non-motorized rotation mechanism, or both.
 12. Athrombus transport system, comprising: a catheter; an elongated helicalmember rotatably-positioned within said catheter; wherein a distal endof said elongated helical member is located near a distal end of saidcatheter.
 13. The thrombus transport system of claim 12, wherein saidelongated helical member has a proximal end located near a proximal endof said catheter.
 14. The thrombus transport system of claim 12, furthercomprising a handheld rotation device coupled to a proximal end of saidelongated helical member so as to cause rotation of said elongatedhelical member.
 15. The thrombus transport system of claim 14, furthercomprising an aspiration device connected to said catheter.
 16. Thethrombus transport system of claim 12, wherein said elongated helicalmember further comprises a passage along a length of said elongatedhelical member that is sized to allow passage of a guidewire.
 17. Thethrombus transport system of claim 12, further comprising a hemostaticvalve connected at a proximal end of said catheter and furthercontaining a proximal portion of said elongated helical member.
 18. Thethrombus transport system of claim 12, further comprising an outer tubefixed over an outer surface of said elongated helical member.
 19. Amethod of transporting biological material from a patient, comprising:advancing a distal end of a catheter to a target location; engagingbiological material with a screw member located within said catheter;rotating said screw member such that said biological material moves fromsaid distal end of said catheter to a location near a proximal end ofsaid catheter.
 20. The method of claim 19, wherein said engaging saidbiological material further comprises applying suction through saidcatheter.